EXAMPLE 1: A drag racer recently tried out a moderate percentage of nitro in his normally aspirated fuel inj. Big Block V-8. The drag racecar ET was faster by about 0.6 second.
An analysis (from our Fuel Injection book, p. 127) determined an increase of approx. 150 HP at the tire. With Pro-Calcs, the setup was determined to be quite rich. The fuel system could be leaned to gain performance.
However, further analysis with ProCalc revealed that a stock 6-71 blower could be added with no changes to the fuel system other than a reduction of the main bypass size. Information from our Nitro book indicated that engine power would go up an additional 200 HP with the blower running the same amount of nitro and same fuel system. The air to fuel ratio with the nitro and the blower in this application was in the ballpark of values that we successfully tested and reported in detail in our Nitro book. With a larger fuel pump, more blower speed could be used for as much as 600 more horsepower at the same moderate percentage of nitro. Going from a low blower speed to a max blower speed for a stock 6-71 blower could not get that much more power on methanol. However, a small amount of nitro amplifies the effect of the blower, and it is a lot easier to figure out with our new Nitro book and calculator.
EXAMPLE 2: Another drag racer ran 7.15 second ET on methanol. The fuel system was richened, and 14% nitro by weight was added. Our Nitro book revealed a power increase of 16% for that amount of nitro. After the nitro addition, the drag racer ran 6.85 seconds ET. Analysis from the Fuel Injection book, p. 127, revealed an actual rear wheel power increase between 13 & 14%. The ET was affected by more tire spin from the increased power. That could account for the difference in power from the predicted higher Nitro book value and the actual lower on-track value indicated by the better ET. The Nitro book info was, however, very indicative of the power level increase for this low percentage.
EXAMPLE 1 & 2 SUMMARY:
1. With our Nitro book, Fuel Injection book, and calculator, power increases from nitro can be predicted and made easier to set up. Power increases from other changes such as engine size, volumetric efficiency improvements, engine speed, and boost can be predicted and made easier to set up as well.
2. With our Methanol book and Motorsports Corrections… book, air density changes can be used to determine accurate fuel system adjustments
3. With our Nitro book and Motorsports Corrections… book:
- HP effects can be determined from air temperature changes
- HP effects can be determined from humidity changes
- HP effects can be determined from air pressure changes.
The effect from each is different. That is explained in the Motorsports Corrections… book and illustrated in our Nitro book. Horsepower management & predictions are valuable for determining:
1. power requirements necessary for setting records
2. bracket drag racing ET targets for land or water racers.
Outlaw Pro Mod Alert
If you or someone you know is considering adding low percentages of nitro to a high-powered racer, our Nitro book has tech info on how much fuel to add for different nitro percentages. It also has tech info that indicates how much horsepower increases for different percentages with the right amount of additional fuel. Both data bases were developed from very effective chemistry analysis and peer reviewed by nitro tuning Pro’s. A lot of the info was also corroborated with testing that is detailed throughout.
EXAMPLE 3: To illustrate this, the addition of 5% nitro by weight to a racing engine is reviewed. According to the Nitro book, power increase will be about 6%. The air to fuel ratio must be richened by a 0.3 ratio number. The Lambda value stays the same. Info is provided in the Nitro book for accurate tuning with air to fuel ratio and Lambda. Several other vital steps for nitro preparation are provided. Ignition and long block assembly info is included. The difference between mixing by weight or by volume is illustrated. All of that is very important in a max effort racer such as an Outlaw Pro-Mod drag vehicle.
EXAMPLE 4: Latest News circa 1968: The DiMatteo family’ new Blown AA/Fuel Altered drag racecar turns 180 MPH in the quarter on 30% nitro (Hot Rod Mag., Nov. 1968, p. 68-69, 74-75).